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Air in Saldanha Bay

Air in 2025 (modelled): nitrogen dioxide near the ground averaged 4.6 µg/m³, under WHO’s guideline of 10; winters 5.4 µg/m³, summers 3.0 µg/m³.

Nitrogen dioxide (NO2) comes mostly from burning: power stations, vehicles, industry. Near the ground is what people breathe. The column is all of it in the air above, from the ground to the top of the sky, which is what a satellite sees. Sulphur dioxide (SO2) comes mostly from burning coal. Ozone forms in sunlight from other pollutants.

Modelled, not measured: these figures come from the Copernicus Atmosphere Monitoring Service’s reanalysis, a weather and chemistry model that takes in satellite readings. Its cells are about 80 km across, so a busy road or a smoky winter evening in one suburb is smoothed into the region around it. It is not a reading at any address.

2025

WHO’s 2021 guideline for nitrogen dioxide is 10 µg/m³ as a yearly mean. It is a long-term health guideline, not a legal limit (South Africa’s national standard for the yearly mean is set separately), and these are modelled regional means, not readings where you live.

Month by month

MonthNO2 near the groundOzone near the groundNO2 columnSO2 column
December 20253.2 µg/m³56 µg/m³36 µmol/m²16 µmol/m²
November 20253.7 µg/m³63 µg/m³43 µmol/m²17 µmol/m²
October 20253.3 µg/m³64 µg/m³41 µmol/m²13 µmol/m²
September 20255.1 µg/m³61 µg/m³43 µmol/m²13 µmol/m²
August 20254.5 µg/m³62 µg/m³37 µmol/m²11 µmol/m²
July 20255.1 µg/m³57 µg/m³38 µmol/m²13 µmol/m²
June 20254.9 µg/m³54 µg/m³36 µmol/m²12 µmol/m²
May 20258.3 µg/m³47 µg/m³44 µmol/m²13 µmol/m²
April 20256.8 µg/m³49 µg/m³46 µmol/m²16 µmol/m²
March 20255.2 µg/m³52 µg/m³44 µmol/m²16 µmol/m²
February 20253.3 µg/m³52 µg/m³40 µmol/m²15 µmol/m²
January 20252.1 µg/m³49 µg/m³31 µmol/m²14 µmol/m²
December 20242.1 µg/m³50 µg/m³29 µmol/m²14 µmol/m²
November 20243.1 µg/m³60 µg/m³36 µmol/m²14 µmol/m²
October 20244.5 µg/m³68 µg/m³38 µmol/m²17 µmol/m²
September 20243.6 µg/m³72 µg/m³35 µmol/m²14 µmol/m²
August 20244.3 µg/m³67 µg/m³31 µmol/m²10 µmol/m²
July 20243.2 µg/m³62 µg/m³28 µmol/m²9 µmol/m²
June 20247.1 µg/m³48 µg/m³41 µmol/m²20 µmol/m²
May 20248.4 µg/m³45 µg/m³41 µmol/m²13 µmol/m²
April 20246.0 µg/m³49 µg/m³45 µmol/m²16 µmol/m²
March 20245.1 µg/m³49 µg/m³40 µmol/m²16 µmol/m²
February 20243.4 µg/m³48 µg/m³32 µmol/m²13 µmol/m²
January 20243.8 µg/m³48 µg/m³33 µmol/m²16 µmol/m²

Over the last five years the NO2 column averaged 37 µmol/m² in winter against 34 µmol/m² in summer, and the SO2 column 14 µmol/m² against 15 µmol/m²: still winter air holds what is burnt close to the ground, and more is burnt to keep warm.

Every year since 2003

2003: 3.4 µg/m³2004: 3.7 µg/m³2005: 3.3 µg/m³2006: 3.5 µg/m³2007: 3.3 µg/m³2008: 3.3 µg/m³2009: 4.0 µg/m³2010: 3.8 µg/m³2011: 3.9 µg/m³2012: 3.7 µg/m³2013: 3.9 µg/m³2014: 4.1 µg/m³2015: 4.3 µg/m³2016: 4.7 µg/m³2017: 4.5 µg/m³2018: 4.2 µg/m³2019: 4.4 µg/m³2020: 5.1 µg/m³2021: 4.5 µg/m³2022: 4.8 µg/m³2023: 4.3 µg/m³2024: 4.6 µg/m³2025: 4.6 µg/m³200320082013201820232025
Nitrogen dioxide near the ground, each year’s mean (modelled). The line is WHO’s yearly guideline, 10 µg/m³.
Show the numbers
Nitrogen dioxide near the ground, the mean of each year, 2003 to 2025: every figure
When or whatFigure
20033.4 µg/m³
20043.7 µg/m³
20053.3 µg/m³
20063.5 µg/m³
20073.3 µg/m³
20083.3 µg/m³
20094.0 µg/m³
20103.8 µg/m³
20113.9 µg/m³
20123.7 µg/m³
20133.9 µg/m³
20144.1 µg/m³
20154.3 µg/m³
20164.7 µg/m³
20174.5 µg/m³
20184.2 µg/m³
20194.4 µg/m³
20205.1 µg/m³
20214.5 µg/m³
20224.8 µg/m³
20234.3 µg/m³
20244.6 µg/m³
20254.6 µg/m³

Every municipality, ranked · Everything we hold for Saldanha Bay · On the explore map

Source

Modelled, not measured: these figures come from the Copernicus Atmosphere Monitoring Service’s reanalysis, a weather and chemistry model that takes in satellite readings. Its cells are about 80 km across, so a busy road or a smoky winter evening in one suburb is smoothed into the region around it. It is not a reading at any address.

How we worked this out

What we changed: we averaged the reanalysis’s monthly means over each place by its area in each 0.75 degree cell, turned NO2 and ozone on the model’s lowest level from mass mixing ratio into micrograms per m3 with the month’s air density (surface pressure and temperature), and the columns from kg per m2 into micromol per m2.

Particles (PM2.5, PM10) and sulphur dioxide near the ground are not shown yet: the model reads them far higher over Gauteng and the Highveld than is plausible for a regional mean, so they wait for a check against ground stations.

Contains modified Copernicus Atmosphere Monitoring Service information 2003 to 2025. Neither the European Commission nor ECMWF is responsible for any use that may be made of the Copernicus information or data it contains. Copernicus Atmosphere Monitoring Service (2020): CAMS global reanalysis (EAC4) monthly averaged fields. Copernicus Atmosphere Monitoring Service (CAMS) Atmosphere Data Store, DOI 10.24381/fd75fff2. Inness, A. and others (2019): The CAMS reanalysis of atmospheric composition, Atmos. Chem. Phys., 19, 3515 to 3556. Under CC BY 4.0.

Dataset: air quality by municipality, release of 12 November 2026.

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